I last did this in 2011 and it involved netloading a ConvertABS.dll file, running the ExportABS command inside AutoCAD MEP (yes you need to actually have AutoCAD MEP) and mapping the IgnoreAbsCodes.txt file. This mapping is an AutoCAD MEP Type to a Design Line type (ie RedInline, Bend, etc). I put in a request for an AutoCAD MEP license through ADN and will get back to you on this if its still there, but all my initial investigations makes me think Autodesk removed this functionality.